January | 2016 | Bonsaiplace

During a conversation with Noel Plowman at the National Bonsai Convention and Show in New Zealand towards the end of 2015, Noel made the statement that it is hard to get good Pine genetic material in New Zealand. Most of the seedlings propagated for the forestry industry is genetically engineered to grow straight trunks with no bark. Both of these factors are not really what Bonsai growers want. We then talked about the thousands of very old Pine trees all over New Zealand, mostly growing on farmland. The photo below shows such a scene, complete with good old New Zealand dairy cows.

This made me look at these trees in a different light and it did not take me long to go and scavenge on a farm (with the farmers permission) to find these original genetic material in seeds for propagation purposes. This I did knowing full well that I am germinating these seeds for the next generation and not myself. The main idea was to collect the cones from trees that show thick bark.

Cones collected, the next job was to get the seeds out of the cones. This basically ended up being a good solid shake of the cone and the seeds fell out. Quite a few seeds were harvested from each cone. The wings were removed from the seeds.

The next step was to find the viable seed. This is done by placing the seeds in a container with water. The seeds that sink are more viable and the ones that float, are discarded.

Top view of the seeds after placed in the water.

Side-view of the container.

The sunken seeds are shown.

I left the seeds overnight and planted the viable seeds the following day. The seeds do have a pointy end and the seed is planted with this pointy end facing downwards. Now the long wait begins as it is known that these seeds can take a long time to germinate and that they do so in a haphazard way. I will update this post as the process unfolds.

Planted and labelled. The long waiting game now starts.

The waiting is over. This was quick. Only three weeks from planting to germination.

The title of this Blog could just be me trying to get as many search terms in the title as possible as the water movement is the same through all plants, large and small. Crafty Blogging! The only difference could be that some plants do adapt to either get rid of excess water and others adapt to try and hold on to as much water as possible. Examples of these in the Bonsai world could be conifers that have needles and scaly leaves instead of large, flat leaves. This is in part to stop water loss, but also for snow to easily glide of the leaves and branches in nature. The smaller surface area means less stomata through which water can be lost.

Stomata on a leaf surface. Water escapes through here and gasses also move through here. These are open.

Smaller surface area for transpiration.

Plants with larger leaves (not really appreciated in Bonsai) do have a larger surface area and more stomata through which water can escape. Escaping water creates a cooling effect as these plants could grow in warmer climates like the tropics where humidity is high as well. Plants actually have to find a fine balance when it comes to the opening and closing of

Larger surface area for transpiration.

stomata. These little structures have a dual function. Not only is it there for water to escape from the plant, a process called transpiration, but they are also in place for respiration to take place. That is the exchange of gasses in (Carbon dioxide) and out (Oxygen) of plants. Both of these processes are crucial for the survival of plants.

For water to move through a plant, there are two main processes taking place. The one has already been mentioned. This is transpiration and it is a pulling force. As water is lost through the leaves, more water is pulled up through the fibres (Xylem). The other process is root pressure. This is a process through which water enters the epidermal cells of the roots, move through the cells and into the endodermis layer. These layers of cells work like a “water pump”. From here the water is pushed into the Xylem. This action takes place against the force of gravity. It is helped by a process called capillarity. This is where water rises up a thin tube due to the adhesion and cohesion forces between water particles. This process can be seen when you place a thin straw in a glass of water. The water level inside the straw will be higher than that of the water in the glass.

It is important to know about these processes when applied to Bonsai. We do a few things to Bonsai that can interrupt these processes and disturb the flow of water through a plant. Also remember that the water also contains minerals and nutrients for the plant. Nutrition will also be interrupted if these processes cannot take place normally.

The first thing we do is root pruning. Not only does this reduce the surface area for water uptake, but it also reduces the root pressure to provide the initial push of water into the plant. This can also interrupt the flow of water and nutrients to a whole branch. The second thing we do is normal branch pruning. This has the effect of cutting off the water flow. Not

A bag around a twig catches water lost through transpiration.

necessarily a problem if the whole branch is removed, but it can restrict water flow to parts further up the water channel. The third thing we do is to leaf prune or defoliate. See an earlier Blog on Defoliation. This obviously interferes greatly with the process of transpirational pull. It weakens the plant and should only be done with healthy plants.

These are things (pruning) that must be done if you want to cultivate healthy, good looking Bonsai. I make the call here to think before we do. Questions that must be asked is whether the tree is healthy, is it the right season, am I doing it for the right reasons, what am I trying to achieve and is it the right thing to do for the specific species? If you can answer these questions positively, then go ahead and cut. To maximise success however, ensure that the tree is placed in the shade afterwards and that watering is increased. Just be careful with the watering when you have partially or fully defoliated the tree. It means that there are fewer leaves to get rid of the excess water. Misting is always an option as well.

Let’s bring Science and Creativity together to create even better Bonsai with a great chance of survival.